Method to geometrically personalize a detailed finite element model of the spine

Nadine Lalonde (1) , Yvan Petit (2) , Carl-Eric Aubin (3) , Eric Wagnac (2) , Pierre-Jean Arnoux (1)

1 LBA UMR T24 - Laboratoire de Biomécanique Appliquée
2 ETS - Ecole de Technologie Supérieure [Montréal]
3 EPM - École Polytechnique de Montréal

To date, developing geometrically personalized and detailed solid finite element models of the spine remains a challenge, notably due to multiple articulations and complex geometries. To answer this problem, a methodology based on a free form deformation technique (kriging) was developed to deform a detailed reference finite element mesh of the spine (including discs and ligaments) to the patient-specific geometry of 10 and 82-year old asymptomatic spines. Different kriging configurations were tested: with or without smoothing, and control points on or surrounding the entire mesh. Based on the results, it is recommended to use surrounding control points and smoothing. The mean node to surface distance between the deformed and target geometries was 0.3 mm ± 1.1. Most elements met the mesh quality criteria (95%) after deformation, without interference at the articular facets. The method’s novelty lies in the deformation of the entire spine at once, as opposed to deforming each vertebra separately, with surrounding control points and smoothing. This enables the transformation of reference vertebrae and soft tissues to obtain complete and personalized FEMs of the spine with minimal post-processing to optimize the mesh. Biomechanics.

Mots clés: METHODE DES ELEMENTS FINIS; BIOMECANIQUE; DEFORMATION

Domaines: Biomécanique [physics.med-ph]; Biomécanique [physics.med-ph]

Nadine Lalonde, Yvan Petit, Carl-Eric Aubin, Eric Wagnac, Pierre-Jean Arnoux. Method to geometrically personalize a detailed finite element model of the spine. IEEE Transactions on Biomedical Engineering, 2013, 60 (7), pp.214-2021. ⟨10.1109/TBME.2013.2246865⟩. ⟨hal-00865166⟩